[1] [1] CIMOLI B,JOHANSEN T K,OLMOS J J V. Microstrip linear phase low pass filter based on defected ground structures for partial response modulation[J]. Microwave & Optical Technology Letters, 2018,60(1):18-25.

[2] [2] GONG J W,LI X J,TAN Q G,et al. Bandwidth-reconfigurable single-passband microwave photonic filter based on stimulated Brillouin scattering[J]. Optoelectronics Letters, 2019,15(1):11-15.

[4] [4] FAN M,SONG K,ZHU Y,et al. Compact bandpass-to-bandstop reconfigurable filter with wide tuning range[J]. IEEE Microwave and Wireless Components Letters, 2019,29(3):198-200.

[5] [5] LI Runshuo,CHEN Fuchang. A tunable bandpass-to-bandstop filter with controllable bandwidth and high rejection level[J]. Microwave & Optical Technology Letters, 2017,59(1):110-113.

[6] [6] HE Z,YANG Y,XI Z,et al. Miniaturized resonator and bandpass filter for silicon-based monolithic microwave and millimeter-wave integrated circuits[J]. IEEE Transactions on Circuits & Systems I Regular Papers, 2018(99):1-10.

[7] [7] FAN S,VILLENEUVE P,JOANNOPOULOS J,et al. Channel drop filters in photonic crystals[J]. Optics Express, 1998,3(1):4-11.

[8] [8] ZHONG Y H,CHENG J B,LI D. Design of a low profile h-shaped slot antenna backed by substrate integrated waveguide cavity[J]. Video Engineering, 2019,43(2):98-100．

[9] [9] HARPER P G,O'DWYER J J. Theory of a dielectric loss in long chain polar compounds[J]. Proceedings of the Physical Society, 1955,68(12):1184-1190.

[10] [10] ALPEGGIANI F,ANDREANI L C,GERACE D. Effective bichromatic potential for ultra-high Q-factor photonic crystal slab cavities[J]. Applied Physics Letters, 2015,107(26):096501.